From patchwork Tue Jun 16 10:05:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 217715 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A73D6C433E0 for ; Tue, 16 Jun 2020 10:06:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82F6820707 for ; Tue, 16 Jun 2020 10:06:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592301984; bh=s5AIqPLMYjaiTPQsq7x7wZzFuQIUauowM5NMNehpPMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0ujReB7FSVrcR6nTEwJ4qx1QAwrPiTIXkKr/5adXFQJ03lW19X12OlZLA8unKu+Ue zwby4BJcyV8GB/ZRU54zGPC/CfRqDcsGtU8owUm3Wbo0FapgvfqnxhzgTucjspB7XG qNXOJSB1WLnHo/T18KGgj7rw2nAGJ3PxcAYpn8Jc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728427AbgFPKGW convert rfc822-to-8bit (ORCPT ); Tue, 16 Jun 2020 06:06:22 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:22179 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728420AbgFPKGV (ORCPT ); Tue, 16 Jun 2020 06:06:21 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-294-1j_u1g3XMPmpIZEatOc1uQ-1; Tue, 16 Jun 2020 06:06:14 -0400 X-MC-Unique: 1j_u1g3XMPmpIZEatOc1uQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9DE191030C53; Tue, 16 Jun 2020 10:06:11 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.195.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id 495195D9D5; Tue, 16 Jun 2020 10:06:06 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Yonghong Song , Martin KaFai Lau , David Miller , John Fastabend , Wenbo Zhang , KP Singh , Andrii Nakryiko , Brendan Gregg , Florent Revest , Al Viro Subject: [PATCH 10/11] selftests/bpf: Add verifier test for d_path helper Date: Tue, 16 Jun 2020 12:05:11 +0200 Message-Id: <20200616100512.2168860-11-jolsa@kernel.org> In-Reply-To: <20200616100512.2168860-1-jolsa@kernel.org> References: <20200616100512.2168860-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Adding verifier test for attaching tracing program and calling d_path helper from within and testing that it's allowed for dentry_open function and denied for 'd_path' function with appropriate error. Signed-off-by: Jiri Olsa --- tools/testing/selftests/bpf/test_verifier.c | 13 ++++++- tools/testing/selftests/bpf/verifier/d_path.c | 38 +++++++++++++++++++ 2 files changed, 50 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/verifier/d_path.c diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index 78a6bae56ea6..3cce3dc766a2 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -114,6 +114,7 @@ struct bpf_test { bpf_testdata_struct_t retvals[MAX_TEST_RUNS]; }; enum bpf_attach_type expected_attach_type; + const char *kfunc; }; /* Note we want this to be 64 bit aligned so that the end of our array is @@ -984,8 +985,18 @@ static void do_test_single(struct bpf_test *test, bool unpriv, attr.log_level = 4; attr.prog_flags = pflags; + if (prog_type == BPF_PROG_TYPE_TRACING && test->kfunc) { + attr.attach_btf_id = libbpf_find_vmlinux_btf_id(test->kfunc, + attr.expected_attach_type); + } + fd_prog = bpf_load_program_xattr(&attr, bpf_vlog, sizeof(bpf_vlog)); - if (fd_prog < 0 && !bpf_probe_prog_type(prog_type, 0)) { + + /* BPF_PROG_TYPE_TRACING requires more setup and + * bpf_probe_prog_type won't give correct answer + */ + if (fd_prog < 0 && (prog_type != BPF_PROG_TYPE_TRACING) && + !bpf_probe_prog_type(prog_type, 0)) { printf("SKIP (unsupported program type %d)\n", prog_type); skips++; goto close_fds; diff --git a/tools/testing/selftests/bpf/verifier/d_path.c b/tools/testing/selftests/bpf/verifier/d_path.c new file mode 100644 index 000000000000..e08181abc056 --- /dev/null +++ b/tools/testing/selftests/bpf/verifier/d_path.c @@ -0,0 +1,38 @@ +{ + "d_path accept", + .insns = { + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, 0), + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), + BPF_MOV64_IMM(BPF_REG_6, 0), + BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_6, 0), + BPF_LD_IMM64(BPF_REG_3, 8), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_d_path), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .errstr = "R0 max value is outside of the array range", + .result = ACCEPT, + .prog_type = BPF_PROG_TYPE_TRACING, + .expected_attach_type = BPF_TRACE_FENTRY, + .kfunc = "dentry_open", +}, +{ + "d_path reject", + .insns = { + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, 0), + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), + BPF_MOV64_IMM(BPF_REG_6, 0), + BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_6, 0), + BPF_LD_IMM64(BPF_REG_3, 8), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_d_path), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .errstr = "helper call is not allowed in probe", + .result = REJECT, + .prog_type = BPF_PROG_TYPE_TRACING, + .expected_attach_type = BPF_TRACE_FENTRY, + .kfunc = "d_path", +},